1. Field of the Invention
This invention relates to circular saws and in particular to guides for stabilizing floating blades.
2. Prior Art
In saw guides, particularly guides of the type of saw in which the saw blade floats freely on its arbor, the guides are usually disposed in counterposed relationship on opposite sides of the saw blade to stabilize the saw axially of the arbor. The lubricant which is most commonly used to reduce friction is water, although some attempts have been made at using an air and water or air and oil mixture.
Some systems of prior art purport to use hydrostatic or hydrodynamic action for lubrication however, such systems have been largely ineffective for reasons of insufficient surface area to stabilize the blade and an inadequate supply of lubricant to maintain a continuous fluid film.
A hydrostatic or hydrodynamic film of lubricant is only effective when it is continuous and stable. Systems of prior art normally include an external pressurized supply of lubricant and have been largely unsatisfactory as they require either a large supply of lubricant or extremely close clearance, less than 0.001 inches, between the guide surface and the saw blade. When the clearance becomes too large a loss of fluid pressure will result and hence a loss of hydrostatic and hydrodynamic lubrication. When air is used as a lubricant this process produces instabilities termed air hammer or whirl.
Furthermore guides of prior art provide a relatively small effective stabilizing area thus necessitating relatively high blade thickness to achieve low vibration levels and hence thin kerf and cutting accuracy.